With millions of people watching, the ISS will glide
over North America during the 2002 Leonid meteor storm.

When the Leonid meteor storm crests over North America on
Tuesday morning, an odd yet beautiful light will appear among
the shooting stars. It'll be as bright as a Leonid fireball but
slower moving and without a tail. And it won't come from the
constellation Leo.

It's really a spaceship: the International Space Station (ISS).

Right: The International Space Station photographed
on Oct. 16, 2002, by the crew of the space shuttle Atlantis.
[more]

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During the Leonid meteor storm, the space station will
fly over North America three times, passing almost directly above
several major US cities. Many people have never seen the ISS
with their own eyes; Tuesday morning will be a great opportunity
to do so.

The table below summarizes some of the best apparitions. It's
only a partial list. Cities not mentioned might nevertheless
have good flybys, so check for your hometown using one of these
three popular websites: J-Pass,
Heavens-Above or
SkyWatch.

The space station shines by reflecting sunlight. This means
the ISS has to be out of Earth's shadow for you to see it. One
of the most remarkable flybys on Tuesday morning will occur over
Washington DC. At 5:10 a.m. EST, the station will emerge from
Earth's shadow almost directly above the capital city. Sky watchers
looking straight up will see the station flare from invisibility
to Venus-like brightness in only a few moments. Such events are
called "space
station supernovas." Another space station supernova
will happen over San Francisco a few hours later, at 5:15 a.m.
PST.

Space Station Spotting
Times for Selected US Cities
*Bold-faced city names indicate places where the sky watchers
will see a "space station supernova."

Above: Local times when the space station will appear
over selected US cities. In most cases, the station will emerge
over the northwest horizon, sail overhead (or nearly so), and
disappear again in the southeast. Sky watchers will see something
different, however, from cities indicated in bold where the ISS
will materialize nearly overhead. Sky maps are courtesy of Heavens Above.

It takes the space station about 5 minutes to cross the sky.
During that time, you might see dozens of Leonid meteors. Those
meteors are much closer to Earth than the ISS is. "Meteors
are specks of comet dust (called meteoroids) that burn up in
Earth's atmosphere about 100 km high," explains Bill Cooke
of the Marshall Space Flight Center's Space Environments Team.
"The ISS, on the other hand, orbits Earth at an altitude
of 400 km." That's why astronauts onboard the space station
have to look down, not up, see the Leonids.

Like Earth itself, the space station will be inside the cloud
of comet dust that causes the shower. Leonid meteoroids race
by the station traveling 140,000 mph--unseen until they hit Earth's
atmosphere below.

Is the ISS
in any danger?

"Not really," answers Cooke. "Most Leonid meteoroids
are nearly microscopic and very fragile. They can't penetrate
the station's armor." Furthermore, he says, "the station
is not a big target. The chances of it being hit by a meteoroid
5 cm across--that's the size of comet debris that causes the
brightest Leonid fireballs--is about 1 in 10 billion."

Above: Tiny comet flakes like this are at the heart
of fiery-looking Leonid meteors. This one is only 10 microns
across. [more]

Those odds are why astronauts can relax and enjoy the show.
Last year ISS commander Frank Culbertson watched the Leonids
from orbit: "There were hundreds per minute going beneath
us, really spectacular!" he recalled in the Science@NASA
story Space
Station Meteor Shower.

You can enjoy it, too, from Earth's surface. And if you spy
a spaceship flying among the meteoroids ... so much the better.

The Science and Technology Directorate at NASA's
Marshall Space Flight Center sponsors the Science@NASA web sites.
The mission of Science@NASA is to help the public understand
how exciting NASA research is and to help NASA scientists fulfill
their outreach responsibilities.

A helpful hint: Web sites like Heavens
Abovenegative
magnitudes. The astronomical brightness scale works like
this: A 1st magnitude star is bright. A -1st magnitude star is
much brighter. The more negative the better. The magnitude of
the Sun, for example, is -26. try looking for the ISS anytime
its magnitude is less than zero.

What makes the ISS shine? There are no bright lights on the outside
of the space station. The ISS shines by reflecting sunlight,
as much as 90% of the light that hits it. Much of the ship is
light-colored. Even the awesome solar arrays, which must absorb
sunlight to power the station, aren't completely black. Their
reflectivity is near 35%.

NASA's Human Spaceflight -- (SpaceFlight.nasa.gov)
Up-to-date information about the space shuttle and the International
Space Station.